Hydraulic resistor



March 27, 1962 M. BEGIAN ETAL 3,026,890

HYDRAULIC REsIsToR Filed April 1e, 1959 ,4195A oF ,4195A of: ow /f/G/f PRESSURE PRESSURE l i as /0 6' I P2 40 l li .h f. f

|l Y l 5o s# 32 52 2o 3@ )D2/ 54W# l k g iR-l X *4 A INVENTORS /f//P//V /A/v ci, By Co/vmo". MM5/AK 3,026,890 HYDRAULC RESISTOR Mehrin Beginn and Conrad E. Miesiak, Detroit, Mich., assignors to Holley Carburetor Company, Van Dyke, Mich., a corporation of Michigan Filed Apr. 16, 1959, Ser. No. 806,881 6 Claims. (Cl. 137-56) This invention relates generally to hydraulic resistors, and more specifically to variable hydraulic resistors which are controlled at least in part by centrifugal force.

In many present hydraulic circuits, variable centrifugally-actuated resistors are employed -to create hydraulic pressure differentials which are used as indications or signals of various operating conditions. These hydraulic resistors have been generally constructed so as to have a main axial driving shaft with radially extending portions adapted to receive a variable orifice valve member therein. Although this design is acceptable in its final operating characteristics, it has been found that the manufacturing methods and practices necessary to constantly duplicate the characteristics as between two or more hydraulic resistors are cumbersome and costly.

Accordingly, it is now proposed to provide a hydraulic resistor which is fabricated in a manner lending itself to easy adjustments and fine control over its ultimate characteristics. Other objects and advantages will become more apparent when reference is made to the following specification, wherein the sole FIGURE illustrates a hydraulic resistor constructed in accordance with the teachings of this invention.

Referring now more specifically to the figure, a housing lil cooperating with a cover plate 11 forms a ca vity 12 which is adapted to receive the hydraulic resistor assembly 14. The assembly 14 is comprised generally of a main driving shaft 16 having lradially extending portions 18 and 20 which are in axial alignment with each other. A tubular valve guide `and seat member 22 is adapted to be received by the portions 18 and 20, and is restrained from axial movement in its ultimately determined position by means of a shoulder 24 and a locking screw 26 which coacts with a threaded portion 28 formed internally of the tubular member 22. A generally hollow valve member 30 is slideably received within Iand coacts with tubular member 22 in a manner so as to form a metering portion 32 at one end thereof. A valve spring 34 is provided internally of member 22 and cooperates with an adjustable spring abutment 36 so as to urge the valve 30 radially outward against the seat provided by member 22.

The housing 10, in addition to providing a bearing surface 38 for one end of shaft 16, also provides suitable conduitry 40 for delivering relatively high pressure hydraulic fluid to the chamber 12. A11 orifice 42 formed at the shouldered end of member 22 provides unrestricted communication of the high pressure fluid within chamber 12 with the metering portion 32. The pressurized hydraulic fluid is allowed to flow past valve 3f) `at a rate depending upon the speed of rotation `of shaft 16 and into a generally annular chamber 44, which communicates with an area 46 of relatively low pressure, as by orifices 48 within valve 30 and orifices S0 within member 22.

Spacers 52 and 54 are provided on opposite sides of radial portions 18 and 2t) so as to radially position the member 22. The primary purpose of spacer 54 is to provide an abutment for shoulder 24 which will result in the correct axial position of member 22 and seat 32; the spacer 52 has the added `function of being a counterweight.

3,926,895 Patented Mar. 27, 1962 ice General Operation Fluid `at some elevated pressure P1 is transmitted through conduit 40 to chamber 12, from where it passes through the metering edges 32 into chamber 44. As the fluid passes through the metering edge 32, it drops in pressure to some lower sink pressure P2 because of the communication afforded by chamber 44 and orifices 48 and Sil.

It is evident that the flow past valve Sil will be some function of the centrifugal force of valve 30 and the spring load on the same valve 30. Generally, when the speed of rotation of assembly 14 is low, the resistance to fluid flow past valve 30 is accordingly low, thereby a1- lowing the pressure in chamber 12 to more nearly approach the value of pressure P2. As the pressure in chamber 12 drops, the pressure in conduit 56 also decreases, thereby transmitting the pressure signal to some remote signal receiving device. A restriction 58, although not absolutely necessary, may be provided within conduit I40 anterior of the junction of conduits 40 and 56. Y

Theoretical Operation It is apparent that whenever equilibrium is attained, (1) Fm=rs+1rc where:

`Ffp=force of fluid pressure `F=force due to spring 34 c:centrifugal Aforce of valve 30 Of course, the force of fluid pressure is:

Ffp= P1-P2 A where:y

P1=pressure of high pressure fluid P2=pressure of low pressure fluid A=efr`ective area -of the face of valve 30;

and the centrifugal force of valve 30 is:

M :mass of valve 3l) Rzdistance from centerline 60 to the center of gravity of valve 30 w=angular velocity in radians per second.

From the above, it becomes evident that Fs is la constant which in no way determines the shape of the performance curve of the assembly. If Fs is neglected, the only other factor is the centrifugal force Fc.

Present designs of hydraulic resistors of this type usually have the valve seat formed as `an integral part of the radial portions 1S and 2t), instead of having it formed in a separate member 22 as provided by the invention disclosed herein. It is apparent that in any such unitized construction, as is the current practice, the machining required to form the seat is extremely exacting. Additionally, the valves, such as valve 3ft, require extremely close tolerances on the overall dimensions and weight. Even though the various elements are machined to within tolerance limits, it is evident that any two assemblies which are constructed from elements machined `to opposite limits will have an appreciable difference in their performances.

Referring to Equation #3, it can be seen that for any angular velocity, w, the centrifugal force, Fc, will remain a constant if the values of M and are respectively raised and lowered a corresponding amount. The invention as disclosed takes full advantage of this relationship in order to provide an assembly which has a high degree of repeatability without the necessity of costly machining and possibly selective assembly.

Referring to the figure again, it is evident that if a particular valve 30 is selected, the distance x, from the centerline 6ft to the seat formed in member 22 will determine the of the valve 30. Therefore, regardless of the mass or length of valve 30, the distance x can be varied in order to obtain the conrect This adjustment is made possible by the provision of la spacer 54 which, in actual practice, can be comprised of multiple layers of very thin shims. By using the invention, it is apparent that accurate machining of the valve seat or valve 30 is not required, nor is the mass of the valve 30 in any sense critical. It is also evident that adjustment of the force of spring 34 can be accomplished independently of the axial position of member 22. This provides a simple method of checking the flow past the valve 30 without having to rotate the entire assembly.

Although only one embodiment of the invention has been disclosed and described, it is apparent that other modifications of the invention 4are possible within the scope of the appended claims.

What we claim as our invention is:

1. A centrifugally actuated hydraulic resistor, comprising a shaft adapted to be rotated, radially extending arm portions on said shaft, a movable member axially slideably received within said arm portion, a valve seat in said member, a valve member slideably retained by and within said movable member and actuated in response to variations in centrifugal force generated by the rotation of said shaft, and means cooperating with said arm portions and said movable member for adjusting said valve member and said valve seat radially relative to the centerline of said shaft.

2. A centrifugally actuated hydraulic resistor, comprising a shaft adapted to be rotated, radially extending portions positioned diametrically opposite to each other on said shaft, a first conduit formed axially within said shaft a passageway formed Within said radially extending portions, a first combination valve yguide and valve seat member adapted to be slideably received within said passageway, an orifice formed in one end of said rst member, a valve member positioned in accordance with centrifugal force generated by the rotation of said shaft and slideably received by and within said first member to control the ow of hydraulic fluid through said orifice, abutment means within said first member, resilient means cooperating with said abutment means and said valve member in a manner so as to urge said valve member radially outwardly yagainst the orice end of said first member, a second conduit formed within said valve member adapted to be in constant free communication with said rst conduit and in controlled communication wit-h said orifice, adjustment means provided between one end of said radially extending portions and said first member for adjusting said first member with respect to the centerline of said shaft, and means cooperating with said rst member and one of said radially extending portions for locking said first member in said adjusted position.

3. A centrifugally actuated hydraulic resistor, comprising a shaft adapted to be rotated, radially extending portions formed diametrically opposite to each other on said shaft, a first conduit formed axially within said shaft, a generally cylindrical passageway formed within said radially extending portions, a combination tubular valve guide and valve seat member adapted to be slideably received by and within said cylindrical passageway, radial passageways formed within said tubular member adapted to be in constant communication with said axially formed conduit, an `orifice formed in one end of said tubular member, a valve seat'portion formed about said orice, a valve member positioned in accordance with centrifugal force generated by the rotation of said shaft and slideably received 'by andwithin said vtubular member to controlthe -flow of hydraulic fluid through said orifice, manually adjustable abutment means within said tubular member, spring means cooperating with said abutment means and said Valve member in a manner so as to urge said valve member radially outwardly against said valve seat portion, a second conduit formed within said valve member ladapted to be in constant `free communication with said radially formed passageways and in controlled communication with said orifice, a shoulder formed on said tubular member, means adapted to be interposed between one end of said radially extending portions and said shoulder -of said tubular member for adjusting said tubular member with respect to the centerline of said shaft, and means disposed at the other end of said tubular member cooperating with one of said radially extending portions for locking said tubular member in said adjusted position.

4. A centrifugally actuated hydraulic resistor, comprising a shaft adapted to be rotated, radially extending portions formed diametrically opposite to each other on said shaft, a. first conduit formed axially within said shaft, a generally cylindrical passageway formed within said radially extending portions, a tubular valve guide mem- -ber adapted to be slideably received within said cylindrical passageway, an orifice formed in one end of said tubular member, a valve seat portion formed internally of said tubular member about said orifice, a fully annular metering type valve member positioned in accordance with centrifugal force generated by the rotation of said shaft and slideably received within said tubular member to control the flow of hydraulic fluid through said orilice, manually adjustable abutment means within said tubular member, spring means cooperating with said abutment means and said valve member in a manner so as to urge said valve member radially outwardly against said valve seat portion, a second conduit formed within said valve member adapted to be in constant free communication with said first conduit and in controlled communication with said orifice, means adapted to be interposed between one end of said radially extending portions and said tubular member for adjusting said tubular member with respect to the centerline of said shaft, and additional means cooperating with one of said radially extending portions disposed at the other end of said tubular member for locking said tubular member in position with respect to said centerline of said shaft.

5. A centrifugally actuated hydraulic resistor, cornprising a shaft adapted to `be rotated, an aperture formed generally radially within said shaft, a movable tubular member slidably mounted within said aperture, an oritice formed within said tubular member for the passage of fluid therethrough, a valve seat formed about said orifice, a valve member positioned in accordance with centrifugal force generated by the rotation of `said shaft and slidably retained within said movable member to cooperate with said valve seat in a manner so as to control the degree of fluid flow through said orifice, adjusting means for positioning said tubular member, said seat and said valve relative to the centerline of said shaft, and locking means located at one end of said tubular member and operatively cooperating with said shaft for locking said tubular member and said seat in said position relative to the centerline of said shaft as determined by said adjusting means.

6. A centrifugally actuated hydraulic resistor comprising a shaft adapted to be rotated, a radially extending body formed on said shaft, a first conduit formed axially within said shaft, a passageway formed within said radially extending body, a first combination valve guide `and valve seat member adapted to be slidably received within said passageway, an orifice formed in one end of said first member, a valve member positioned in accordance with centrifugal force generated by the rotation of said shaft and slidably received within said first member to control the iiow of fiuid through said orice, abutment means within said first member, resilient means cooperating with said abutment means `and `said valve member in a manner so as to urge said valve member radially outwardly against the orice end of said irst member, a second conduit formed within said valve member adapted to be in constant free communication with said rst conduit Iand in controlled communication with said orice, adjustment means provided between one end of said radially extending body and said iirst member for adjusting said first member with respect to the centerline of said shaft, and means cooperating with said rst member and said radially extending body for locking said rst member in said adjusted position.

References Cited in the file of this patent UNITED STATES PATENTS 

